Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)

Ignition
1

Hello everyone, I have very little experience with DB connections and I am having problems trying to connect to a MySQL DB from a seperate machine.

The error details are:

org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1225)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880)
at com.inductiveautomation.ignition.gateway.datasource.DatasourceImpl.getConnectionInternal(DatasourceImpl.java:242)
at com.inductiveautomation.ignition.gateway.datasource.DatasourceImpl.runTest(DatasourceImpl.java:196)
at com.inductiveautomation.ignition.gateway.datasource.DatasourceManagerImpl$FaultedDatasourceRetryer.lambda$newRetryRunnable$0(DatasourceManagerImpl.java:998)
at com.inductiveautomation.ignition.common.execution.impl.BasicExecutionEngine$TrackedTask.run(BasicExecutionEngine.java:565)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.runAndReset(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836)
at com.mysql.cj.jdbc.ConnectionImpl.(ConnectionImpl.java:456)
at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294)
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1221)
… 12 more
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.GeneratedConstructorAccessor143.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105)
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151)
at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167)
at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:91)
at com.mysql.cj.NativeSession.connect(NativeSession.java:144)
at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:956)
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:826)
… 19 more
Caused by: java.net.SocketTimeoutException: connect timed out
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:155)
at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:65)
… 22 more

7.9.9 (b2018081621)
Oracle Corporation 1.8.0_271

I can read/write into the Database from other aplications but I cant in Igntion

Some things i already tried:

  • Ensured the username and password matches the one I use in my DB and has all the privileges granted
  • Added bind-address=“0.0.0.0” in MySQL
  • Updated MySQL ConnectorJ driver

Ignition version: 7.9.9 (b2018081621)
Java version: Oracle Corporation 1.8.0_271

2

Pure network issue. Firewall, perhaps. Or, more likely, the target database is not listening. IIRC, both MySQL and MariaDB default to listening only to localhost.

1 Like
3

If you’re using Windows, you’ll also have Windows’ default firewall blocking external access on the port MySQL uses.

4

Thanks for the reply. My DB is running on a Raspberry Pi 3 with Ubuntu. As far as I know there is no firewall installed by default

5

Is your gateway on Windows? If so, does the service’s user have network privileges?

6

Yes it is on Windows
Not sure if I understand the second question correctly
The username I am using to try to stablish the connection is “Leonel” and I used the comand "GRANT ALL PRIVILEGES ON . TO ‘Leonel’@’%’; " in MySQL to give him privileges

7

No, I mean the user of Ignition itself. “LOCALSYSTEM” is typical. Which often does not have network privileges.

Also: You said other apps could talk to MySQL. Were they on the gateway system, or in the RPi ? If the latter, double check the RPi’s firewall, and use netstat -l to verify MySQL’s listening address.